Leadframe assemblies for electrical connectors are well-known. A typical leadframe assembly includes a dielectric leadframe housing and a plurality of electrical contacts extending therethrough. An insert-molded leadframe assembly (IMLA) may be manufactured according to a process wherein a leadframe is stamped from a sheet of electrically-conductive material, and a dielectric material is insert-molded over the leadframe.
Typically, the electrical contacts within a leadframe assembly are arranged into a linear array that extends along a direction along which the leadframe housing is elongated. The contacts may be arranged edge-to-edge along the direction along which the linear array extends. It may be desirable to form differential signal pairs wherein the contacts that form the pair are broadside-coupled (i.e., arranged such that the broadside of one contact faces the broadside of the other contact with which it forms the pair). Broadside or microstrip coupling is often desirable as a mechanism to control (e.g., minimize or eliminate) skew between the contacts that form the differential signal pair.
It is usually desirable to maintain a desired impedance between the contacts that form a differential signal pair, and to maintain a constant differential impedance profile along the lengths of the contacts of the differential signal pair from their mating ends to their mounting ends. It is often desirable for the mating of the contacts to be “sequenced.” That is, it is often desirable for certain contacts to mate before, or after, others. Usually, to produce a connector that defines a multi-tiered mating sequence, contacts of different lengths are employed. The mating portions of longer contacts may extend farther in the mating direction that the mating portions of shorter contacts. For example, ground contacts may be made to extend farther in the mating direction than signal contacts so that the ground contacts mate first, thereby establishing a common ground between the connectors before any signal contacts mate.
The leadframe assemblies are typically inserted to the same depth relative to the mating face of the connector housing. Therefore, different leadframe assembly configurations may be required to produce certain desired mating sequences. For example, if a single contact in the connector is to be a “short detect pin,” that contact would have to be shorter than any of the other contacts in the connector. The leadframe assembly containing the short detect pin could not, therefore, be identical to the other leadframe assemblies. This causes a need for different leadframe assemblies to be designed and manufactured. It would be desirable if a single leadframe assembly configuration could be used to produce a desired mating sequence.